package com.itheima.Filter;

import com.itheima.utils.CurrentHolder;
import com.itheima.utils.JwtUtils;
import io.jsonwebtoken.Claims;
import jakarta.servlet.*;
import jakarta.servlet.http.HttpServletRequest;
import jakarta.servlet.http.HttpServletResponse;
import lombok.extern.slf4j.Slf4j;

import java.io.IOException;

@Slf4j
//@WebFilter(urlPatterns = "/*")
public class TokenFilter implements Filter {


    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        HttpServletRequest request = (HttpServletRequest) servletRequest;
        HttpServletResponse response = (HttpServletResponse) servletResponse;

        //1 获取请求的url
        String requestURI = request.getRequestURI();

        //2 判断是否是登录操作如果url包含/login，说明是登录操作，放行
        if (requestURI.contains("/login")) {
            log.info("登录操作，放行");
            filterChain.doFilter(request, response);
            return;
        }
        //3 获取请求头中的令牌(token)
        String token = request.getHeader("token");

        //4 判断token是否存在不纯在说明用户没有登录，返回错误信息401状态码
        if (token == null || token.isEmpty()) {
            log.info("令牌为空，响应401");
            response.setStatus(401);
            return;
        }

        //5 token存在,校验令牌。校验失败返回错误信息401状态码
        try {
            Claims claims = JwtUtils.parseJwtToken(token);
            Integer empId = Integer.valueOf(claims.get("id").toString());
            CurrentHolder.setCurrentId(empId);
            log.info("当前用户id为：{} ,将其存入ThreadLocal", empId);

        } catch (Exception e) {
            log.info("令牌非法，响应401");
            response.setStatus(401);
            return;
        }
        //6 校验通过放行
        log.info("令牌合法，放行");
        filterChain.doFilter(request, response);

        //7删除ThreadLocal中的数据
        CurrentHolder.remove();
    }


}
